story identification - Movie ID: 50s/60s time travel film with *terrible* plot holes

Back in the eighties I saw an apparently sixties-era film on afternoon UHF TV. In it a crew of men and women were on board a time-travelling vessel. I think it was not a ship, more of a stationary pod a la H.G. Wells' time machine. Through the film the crew finds themselves in troubling time-related predicaments.

I remember two of these situations, only because even at my young age it was clear to me how illogical these situations were and how great the plot holes were.

One of these situations occurred when the crew time-travels to their own recent past--a previous scene of the film, I think. But the "past" version of the crew is frozen still, and the "present" crew comes to realize it is because time is flowing for them at a greatly accelerated pace, so that the world around them is almost, but not completely, still.

Later the crew travels again to the past. While in transit to the past, the crew discovers their vessel is on a collision course, through time, with another vessel. They attempt to hail it, and fail. The only way they can survive is to fire on it, so they do, and the other vessel is destroyed, though their own takes damage.

The crew arrives in the past and they do what they set out to do (I forget what). Then they board again, to return to their own time. And on their way, they again discover their vessel is on a collision course with another vessel. And the other is hailing them! And they hear their own voices! And their transmitter is damaged so they cannot reply! The conclusion of that scene may have been left to the viewer. And all that was while they are travelling through time, in a vessel that, as far as I can remember, never spatially moves during the film.

The only reason I remember this obscure, poorly produced film at all is because the plot holes are so gaping and obvious. But as to its name, I completely fail to recall.

Answer

It looks like the movie you're thinking of is "Journey to the Center of Time," from 1967, directed by David L. Hewitt, starring Scott Brady, Anthony Eisley, Abraham Sofaer and Gigi Perreau.

Overcome by greed, Stanton grabs handfuls of the precious gems, returns to the time machine, replaces the ruby and takes off without the scientists. However, on his return trip, he encounters another traveler in time. He hears a radio broadcast — it is from Manning! He is racing towards the earlier version of the time machine. Then he is destroyed by a blast initiated by his earlier self.